feat(product-center): implement Figma-designed UI, upload module, and website tests

- Redesign website homepage & product-center per Figma (fonts, logos, hero/footer/customer cases)
- Add API upload module (multer) with static serving for uploads/public assets
- Add OriginGood.delisted flag and SDS request retry logic
- Add admin ImageUpload component and goods import/upload flows
- Add vitest suite for website components and composables (32 tests)
- Add skills, docs, plans and PRODUCT.md

apps/website/app/components/product/ProductCardSkeleton.vue

@@ -1,6 +1,6 @@
 <template>
   <article class="skeleton-card">
-    <div class="skeleton-media"></div>
+    <div class="skeleton-media"><i class="fa-solid fa-image" aria-hidden="true"></i></div>
     <div class="skeleton-info">
       <div class="skeleton-line title"></div>
       <div class="skeleton-chips">
@@ -31,10 +31,14 @@
 }
 
 .skeleton-media {
+  display: grid;
+  place-items: center;
   width: 100%;
   aspect-ratio: 1 / 1;
 }
 
+.skeleton-media i { position: relative; z-index: 1; color: #c2c2c2; font-size: 44px; }
+
 .skeleton-media::after,
 .skeleton-line::after,
 .skeleton-chip::after {